nanoflann 1.2.3 (new formula)
nanoflann 1.2.3 (new formula)

Closes #6139.

Signed-off-by: Shaun Jackman <b580dab3251a9622aba3803114310c23fdb42900@gmail.com>

pditommaso/homebrew-science,andrewjpage/homebrew-science,heuermh/homebrew-science